As a guess, you might have directory damage. Have you tried booting from the Recovery partition and running Disk Utility's Repair Disc function? Do you have Disk Warrior, TechTool Pro or Drive Genius? If DU can't repair it, one of them may be able to.
Jon
macOS 11.7.10, iMac Retina 5K 27-inch, late 2014, 3.5 GHz Intel Core i5, 1 TB fusion drive, 16 GB RAM, Epson SureColor P600, Photoshop CC, Lightroom CC, MS Office 365
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